Antibiotic-Induced Colitis: How the Gut Microbiome Is Impacted by Modern Modern Medicine

January 04, 2018

The use of antibiotics is all too common in modern medicine, with risks that are becoming increasingly evident. While they are literally life-saving in many instances, no drug is without potential side effects.

One of the more frequent and dangerous consequences of these medicines is antibiotic-induced colitis. Affecting roughly 500,000 patients per year in the United States alone, antibiotic-induced colitis is a risk factor for anyone who has taken the medication. Symptoms of gastrointestinal diseases and disorders have been reported in patients both young and old after antibiotic use, with this risk increasing over time with each new exposure.

Throughout much of medicine’s history, and certainly in the case of antibiotics, bacteria have been presented as the cause of disorders and something to be eliminated. While true that some can cause infection and disease, scientists are finding compelling new evidence that many of these microorganisms are not only beneficial but, in fact, vital for health as well. The use of antibiotics, then, must be reevaluated in light of these discoveries about the gut microbiome and its relationship to antibiotic-induced colitis.

The Gut Microbiome: An Ecosystem Living Within

A vast collection of bacteria, viruses, and fungi inhabit the human gut, creating complex ecosystems, known as microbiomes, that promote health and vitality. Not only do they aid in digestion, they also guard against colonization by harmful bacteria. Only in the last few decades, however, have researchers begun to understand the complexity of the bacterial ecosystems found in the intestinal tract—and the intrinsic nature of how a balanced gut microbiome impacts one’s health.

New evidence suggests that a spectrum of disorders, from obesity to mental illness, may be influenced by the bacteria found in the gut. Given the complexity of this microbiome, and its mutualistic association with human health, is it any wonder that antibiotic medication can have a deleterious effect? These medications not only affect harmful bacteria but significant populations of normal gut flora as well, disrupting the gastrointestinal ecosystems. This allows harmful bacteria to colonize within the gut. When this occurs, these harmful bacteria can cause an array of illnesses, from diarrhea to antibiotic-induced colitis and even cancer.

Paradoxically, the standard treatment for antibiotic-induced colitis is to administer yet more antibiotics, with dismally predictable rates of recurrence. However, as research reveals further evidence of the importance of the microbiome of the gut, particularly its ability to prevent intestinal colonization with pathogenic bacteria, several medical professionals are considering complementary or alternative therapies focused on augmenting the gut microbiome. Recent data suggests that the rapid repopulation of healthy gut flora yields more successful results for combating antibiotic-induced colitis than do traditional pharmaceutical drugs.

Antibiotic-Induced Colitis: Why the Gut Microbiome Must Be the First Line of Defense

One of the most basic components of one’s well-being is a healthy diet; the microbiome of the gut will interact with, and be affected by, everything eaten. Fresh fruits and vegetables, legumes, and complex carbohydrates all help the bacteria in the gut thrive. Additionally, fermented foods such as yogurt, kafir, and doogh have been used for centuries to support health, acting as probiotics and delivering beneficial bacteria to the digestive system, bolstering the gut’s microbiome.

Occasionally, however, when a patient’s gut microbiome is dramatically out of balance, a healthy diet just isn’t enough. Sufferers of antibiotic-induced colitis who are experiencing severe damage to the flora of the gut require a more direct approach for restoring its vitality. This is where probiotic supplements can help alleviate symptoms by delivering living bacteria directly to the gut and repopulating the microbiome with beneficial organisms. While probiotics have come into common use, much less discussed and utilized are prebiotics.

Unlike probiotics, prebiotics don’t contain bacteria to repopulate the microbiome; instead, they provide vital nutrients to existing populations of beneficial bacteria in the gut, bolstering their proliferation. These nutritional supplements, such as pectin or inulin, consist of naturally occurring compounds found in foods high in indigestible fiber. While indigestible to humans, certain species of gut microorganisms, such as bifidobacteria, thrive on these molecules.

Furthermore, as the bacteria metabolize prebiotic compounds, the products of this metabolism become bioactive. Some of this bioavailability allows these molecules to be absorbed by the human host, providing increased nutrients. Other products of metabolism are bioactive in other ways, such as having antimicrobial qualities against invasive and pathogenic bacteria. Often, prebiotics and probiotics are given together, the two acting synergistically to rebalance the gut microbiome, offering an effective and natural treatment for sufferers of antibiotic-induced colitis.

In extreme cases of antibiotic-induced colitis, a procedure known as a fecal transplant has been shown to quickly repopulate the recipient’s gut with helpful bacteria, successfully restoring the microbiome. As the name implies, the procedure involves taking fecal matter from a carefully screened donor, then processing it to a more refined material to be transplanted into the gut of a patient. The goal of the treatment is to transfer the microbes from a healthy gut to an inflamed and damaged one, using them as the seed from which the gut’s microbiome can be repopulated.

In one study, five hospitalized and immunocompromised patients, all suffering severe intestinal symptoms following antibiotic use, were given fecal transplants. These patients saw a resolution of their symptoms in mere days—and remained symptom-free for years after the treatment. Currently, antibiotics are the first line treatment for antibiotic-induced colitis, but the successes seen with fecal transplants have many in the medical community advocating for the procedure to be more widely implemented.

Antibiotics are a common tool in modern medicine’s armamentarium, with no indication that this will be changing anytime soon. Antibiotic-induced colitis, then, can be expected to remain a challenge doctors and hospitals will continue to face. Add to this the increasing resistance to antibiotics themselves in some antibiotic-induced colitis patients and the need for alternative methods to fight and prevent the disease becomes evident.

Studies have demonstrated that repopulating the gut microbiome, whether through dietary modification, prebiotic supplements, or a fecal transplant, is a valid approach to combat this illness. Given how active an area of research this has become, and the positive results of these studies, it’s likely that additional microbiota-based therapies will continue to be developed.

The ability of the gut microbiome to resolve conditions as serious as antibiotic-induced colitis appears to be close to miraculous but, in reality, is quite natural. Given the expense and risk that accompany the overuse of antibiotics, some medical professionals are beginning to consider alternative and complementary approaches to gastrointestinal diseases and disorders which support the microbiome, as opposed to devastating it. With current research demonstrating how important the flora of the gut is, this will continue to be a topic of interest for the medical community. This expanded understanding of the gut microbiome is certain to guide future therapies for antibiotic-induced colitis patients.

Foundational Medicine Review is dedicated to introducing new therapies targeted at gastrointestinal and neurological disorders, such as antibiotic-induced colitis, which have their root in the gut-brain axis. We believe that bioavailable nutraceuticals are the foundation of health—and that alternative medicine is no longer an alternative. Join our e-newsletter list to receive more articles like this directly to your inbox on a monthly basis.